The problem is a lack of other options, driven by the incentives and actions of payment processors like Mastercard. This isn't just theoretical; those who tried switching to Subscribestar after the Sargon incident immediately lost their income again as PayPal cut ties with Subscribestar. The whole "it's a free market, build your own platform" excuse for deplatforming gets increasingly weak as the deplatforming moves upstream towards regulated oligopolies like the international payments system.